SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2f6b1899e22225ff7802dcbb86b374a0b29840da983ccfac8168d0fc934db0e4' 
  AND token = 'kyEYadApkM4ObaRhMO/TtLmQqSEkyNoAM9M2c6hbIXU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}