SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3ca6a196d0932ced4d3a5d779d51fd3e09eb927d5042e80eb408cac607fd81ba' 
  AND token = 'ZecaUfbBkbyQJGjA0UocKntpfzzk3GtZCj16EU7aIfY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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