SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '987726ca9e243cac549bec78fa3f529218ea1c43117a1e9fe3979a2407dde98d' 
  AND token = 'vmbXDyOuQTUaVajLVT90AvTpRDSHqOxx9faQteNGURg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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