SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '7bc35e0d69676ab3b2c4946b62ac0f1a3719d5bb7dffe5cd3cdea82cd08869ce' 
  AND token = '1+XMlyGUuIrlKFI7x5mDqTSP448c/+gQfW+xnRT0Uq4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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