SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'edd4178fbd511cae8dc5726183955a582ab9c8c27af69f77f7ea131a614efeea' 
  AND token = 'FPbAVXrKTTbdYVZ3LKvIIUepjrOHaJbmaswGwvYPlZQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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