SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0c4c89f5ad7d227c76c1b43794088fed73ba2b38e8884b9975321907906da12e' 
  AND token = 'x066GzFeAP5vAWnV88ZvvoddJSflcr936gFwigTappY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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