SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '23220a7817939607344a0b1a6cd683bc2d1da4f0519de15bc41e15e4df1c5a5f' 
  AND token = 'e8RfDuBYoVSU2FCjlFf8uKD0xHywLHPI1T/58FKGhFQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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