SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '0086d938891936d29467ce9c2fffd0378a4b043e21ca37a58addf3e1b8ec184e' 
  AND token = '7QZL1/DTo0u+fFwo4RG+qGTeXHmtwQsVLdTo2CzzFaY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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