SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'df6ed034f4981c4bbdd5426fad52f224d4cf1ea1593b0dea8b13bf8867bef42f' 
  AND token = '25BXiQ8pISts5+wLQo0Bt5o07MZ4O08NwyciwYANkCk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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