SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fde5b5aa268a66211fb41136943cd95172f4d5b6dbfb5a80ddaf2f866d1d8167' 
  AND token = 'AHTuV7+0s7+VxT6VC5aBN6AIATwwGObmsd/n3IcvNGI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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