SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '7eb569cd4094360ed95e22a9a01423204ffa060b2928938130c862222e4d9180' 
  AND token = 'xae+jdRABhZq6kzkywJdHLcnZGMyz1wv7FHWQdpH4y0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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