SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '85c87d5475000f08816d3daf062d19ad0126f41b28641c755c12c60f006de2d2' 
  AND token = 'PRDAVCZkHkKPreLGFKC0K/QlrwZEDS+dcTNkglvpKQU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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