SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ba4ba397648dfaadb36c95dc84c9dd35b841a6116624f3e725707db2af0f61d5' 
  AND token = 'hg5qKpS11m1c6o+19QvCAjQIgZT4BGmux1KRw/pS29M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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