SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd29afe33b78a2954e0d2f6d6596a6178d3e47c89553968d576e2db85c313048a' 
  AND token = 'jjul24efmOz7TEAw5NZV0mMFYJS4ksn/POwgU38Fwwg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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