SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '231ca819f298c7947d3f00aeb156f5495cb789d0589a95df2dd838a71e65de85' 
  AND token = 'YAFErhLGqNRSzhykd3KjmAKxWM9Q5qnw+hnOou5CWtQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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