SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'efaa9b072a73e1efa9e5281de8cce21f979ed0c1e1d0d9f1e42564a10414b58b' 
  AND token = 'XrdI+2L3yUTH0QEInkqE8tk+UxCm5Ayr/MDUnOJFFGk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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