SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0b5684e9249cce7d1e06b334b89709823a53f454ab48991ce84aba69e2225ef5' 
  AND token = 'hiqQ0/rWgb+jCKI5cDU0twMcQ7a1MJDPYIMw5TueaDI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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