SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '94ad9f688ddca5fb073320387803e5cbea0883235cbd7d4c02483d42203e1bda' 
  AND token = 'DEVH1iQOx3QZ6CIJBHm1REhg0wZFpo9/Z/YDHaRHNy4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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