SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58a414f698044f1a9f6274b1d73eb5387bdb01b2328f3ebe3a05c13aa6566619' 
  AND token = 'GzCk9FrjVGjcOBC/nD+EeUSYVLSz7Xcuxwql+QLKnXo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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