SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6d980984d5792fa8426fcdd93d4964473ce0288b23207cbdc9eb89a27944ea89' 
  AND token = 'jg9P3RZ0pm894db1Bh5nLfQ+08uACwkUbNZA3vl6zUY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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