Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b721cdc95ff0678988333f51ac0183cafdf66d38eba204bd44ad0935c2cc880f' 
  AND token = 'mbzCzDdITYZfyjuhIxASscWz3XpWv0DY07ePutT0Yec=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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