SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e1a4d2c5bc32daf9671fd0393be58ac3a2222ec2491ce9bdac2d7524d637b375' 
  AND token = '0VrbXxQeNFYZCORvWyZa2GdWxgDjisKWouBziWA1qos=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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