SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '85040d08013a09a6df6a23d3d2443cd6b7ea5f8e63ba62746461653cd471222a' 
  AND token = 'GVLTFdV4hsASc15/DFFZDtFHI3M+qFTeP0yIewSWMZ0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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