SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '80136c57d2152bd8e5b5487388be6a981f6f9efdc33cf3cc05b9e7c6364acc53' 
  AND token = 'O6DgwHxEv+ziC+ZGuXGrVQmw1syW3pjbW4TiWyDVoH0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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