SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a0aec5c210a54a8166f6098d5b7e52619f09bb801e3eade3a29a3e942a2bc724' 
  AND token = 'Th+W6HNw/+NGbKq1JHiy61wG09eM0360j33D008OBQw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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