SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3172d2245bfcf787d09bd89d5b6456cb5449a15f453e7274e42b2fb9bd847432' 
  AND token = '6ktlp+HDXqYKlJyafL/TC3fBPntzImPhegL1Ijjy7P8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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