SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c19733a3f6a5b99ef5be4a673c1074114108ef09649dd1f2d191d460d3f99a29' 
  AND token = 'YJR/yuaChwgpfeNvROxaAsbmtxsYpsM/JfaRwhWoeck=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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