SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7a479065f341f46591b7976ee6d1e2dda672a427e75b38864496b3d487b43713' 
  AND token = 'sJhKMAZoSJ7kqYmMBBAwXLwZ5AVR2nX0ZHO33A0ZLag=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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