SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cf534b3b40bd748f47e7d5f958ba09632f368818c66d78496fb687fec7d2e262' 
  AND token = 'BQBf3Y+CXMKYoSkpsWuk5ZKMc/jrVCUrZg+CxVqIXoc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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