Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b5875e9fc641d6c321c4534b83dee79a1e7421eb88d0c2ef4098e1a62fb58153' 
  AND token = 'g4T7ynxij9KPOCoVIMS+so4+HCKNQFcB3fn/l+zG1R4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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