SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1cfc7032c182166030fb526f0a19d287bbf49ea654b8337fd8a417a40c5f737c' 
  AND token = 'HL1GYaplINVFrQIUdLf9dL7shV4aDqIUno3lpixYuVw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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