SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '77bcac0e6ce8d20fdc343a83d6af88798aa33e8d04325d8f4301e9216ea1f6c8' 
  AND token = 'sVqKJOCtcNTL3E+YdkzGZsw1OOniXDPNxpGP473BmEk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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