SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '785f387fa6bd7caef768a67812adf95f4c5c9ddedc5b0273188fa5df39c3d6d9' 
  AND token = '41wIEssF/Ybh/LFSYTuDWL6+glaiZ4zOAQKrr5eX/NQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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