SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2464b17c10ad9bc2b9da41ead9dd10279fc7972bf6bbc0095d602c9c7cf17e6e' 
  AND token = 'LD1hDAhhrt8T2ZHdFZ8mQhnVXF+TKwq5kHmqBdxnPEY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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