SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c1f6917afb60f40295a11a83b231ffca4e335bed8b6e0c660986b002d4454a7a' 
  AND token = 'Whi0q7PRSNuT9JEVnIEmBzWYa6NLOzpEIz1wMexrZ+c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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