SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'b5156934bd21460723ff06890231bb5f2a4ee8d9f064782ed52fd9d2fd57409a' 
  AND token = 'aedTogB5QGx9lXIPgoL6W8PrJ2Wmw/P5fyr5gKtVgM8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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