SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '657456801a555bcc840c9317143e8ec0a65b41eb4091fa926a412dcb242f0021' 
  AND token = 'PhHGJMUrgqCRQO6U0Y64CqurvLI5um+hRNCoM1V6LLE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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