SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '70be0ff660b922c9d3ee557d364424977d3d23c597daf8c7d2acd1a48f085e2a' 
  AND token = 'r4yFwLSuHQRVFKRdirbbl5vX3GImswHc9QkrwcqGYmg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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