SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ceee5b0d460c9673147dd3babb80cdfd107100ec96317d3cab78b57b67f7265b' 
  AND token = '7aQyhbdRqPUFfayy/qlYxl5JB5UlJDtMAqdEkpAeKbE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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