SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '73683155e528883160aa97f0a4199e473e607a6ba03cbb75e65e17ef3a5bc201' 
  AND token = 'XvBfNlbHmEzK7L3gTv1eeAPkGF3syFFBQE/ohGUFJMM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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