SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a8f4abe7c6618835fe70279bd25a16dea2b0d8480b5f8f70d163d4875d31b1fa' 
  AND token = '1xBbsiIyoTL0oiubh2jW6RZosOZdufKlVt1bdo+bOF0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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