SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '54401083067b385ffbd1894e6c5bff81883b84dead6bf41176f50398007a12ba' 
  AND token = 'dsIk1UHAoSbyzPVPIoHDsyGNxi3A8y82bbZeV/EnZfs=' 
  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"
    }
  }
}