SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '079add2c9fe76541d2e68ae56339757c8a2aa7205ff1a890f55cbcb8aafe173d' 
  AND token = 'sqxhpzf0Nxm1dT7YNbJbfRxZo+4Lhg7TUPWXjd8TyB0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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