SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '637413b8917bf2511d81232bc6d6369fec2bf733cb0c212c285ae2f3118969b2' 
  AND token = 'vPghxI0D8cVfiocBQQvpsmAMlYbqLjDzKkf41+5keXU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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