SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '158dba014262bfa4f359fb8db8d8572bcc31e48cdae497a375138c65749816a8' 
  AND token = 'hw4MSPVOIcF3VD0fp62O2EF7ZkrztCfaFSko9j0Cxnk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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