SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '8faacb7ea728c76d049654730bdf9e65a66bd45333fb6552665d5546c4851c08' 
  AND token = 'pJKuhnC/k3ib6nEP/XOqns+ZluY/MMfUe32hOspt9yY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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