SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '0d2b3c86104391e3455917092445e1da9ac5ad2d8179f7f6cb8f1a6f6e8af5cb' 
  AND token = 'dyfAxo+sdP2d8Ri77hw4kjJA0aIu4o7mbHwDD17ikCM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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