SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6d1e4d3244f9336e5a0da6385d3bda7557b4dde5823400a0e12d2d0a050ffb2e' 
  AND token = 'OkL6RfD9lhTXN8t2d5/fAc9qe7yGyYw3x2lJVkLqIEc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00075

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}