SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'eb5e8becb0bd842fade13a5387a5b6661798e80752149bc67ad566f6dfcc7b73' 
  AND token = 'Kr2l2pJKidBZG231/OgxrVdGKRtxVCWWUIELX3f+1Cc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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