SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '185342c2bf5140b9f3af18201537c1f6ebaa8acca07dd30e90e69b6f426c2a4e' 
  AND token = 'exFj8hC3O/pqb1ZdlZQnTSVqY3JGRCwgov/lewYEduw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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