SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1926795ab683c361ada8f641f8d09e62eece76abd8694d40d02e8c0a92401902' 
  AND token = 'fooRfLchaWq5qgdJmIVfkbHHtSQhNCLgl0foFCUftIc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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