SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c1c307c06fb11342ee606a622056dd48148c2c8149d7989bbb7bf336f6b26f76' 
  AND token = 'WRmXqJ2GMZ5I2PomTKPuwV9LhpvW1lpcaCREfm+Ao+Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}