SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6d2a783eb6b1a23683cf56d76ee857e06ed1ed2e778767d4ef646194b5945534' 
  AND token = '+ah94li2MBV41hNYCxlJgLtBWRcny7IvzY9HIKGqkKc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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