SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '239426d51357c422c8cb074854f28362633f9cc5c402ead11e955acf66c718cb' 
  AND token = 'gvYlXqQogZJNrKaIf1VqWQwjQjlwaOMkeaW1kCEbh08=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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