SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e2b114b6a89687c0da874ba06b1327de64ba9506a2fc4b799d2da7f3fb5a0923' 
  AND token = 'Z7gBIJliwozPeEw8F0UO9RVLfSA5RBWRaOauMIOx+kk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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