SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ccb94709464d537a39ea2b22ec1d235df2a73042e2e41aa19ded408e4ee9fdd4' 
  AND token = 'MygrWEqbi/pw6UHPAa3ckvhbIvFx2fDdjZls55JD1J8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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