SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1f9bbfcd1e92d63beae1d9fdfb8220d767f7b8b436a7224f70a08db2306b0d9d' 
  AND token = 'jULUqsZphSLzQu7oJ4ZJoLE6MnEjvGiWumSVUMiXnJ0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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