SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f9cdabb7ac8b12b61f6ddae8163cdacbb2d268f7298817e10cc27e25a91f94ba' 
  AND token = 'RcR60m1PJvEpyRiqcyVnnQ3Pfv86BFWw29wij2W/dIU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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