SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a629ded247324bac3f18b4c22c6fcfeb2ca84495f89f90d356f7e2d910f11250' 
  AND token = '1liINBZE1VjaDj8ltPzPwLK9yINpOLcbtLhOVYsfZFg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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