SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '27e03dfd5e7fbb5e203a37fdca88dc0b11ae72ebd2e995c602c74435b7668c79' 
  AND token = 'ri5BijxlsVonhw4q1itGwC9WZ1U6EEUItGd3e2vgwAQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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