SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4bc3403809a44dc8986632232759bcd8179eaa2cec80f3aa0d1af8db9166e02b' 
  AND token = '4EGqnovzh6Qn3Icmki0eVA+yJkqePqWNt3FXttHBQ8g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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