SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '61ec2d3d6fdd60f679618234ad9caa5c163beb725287c95e78054ea1c9a11e59' 
  AND token = 'wyDcqh8+rlxIqoBMM0jNxXPus2vjMkY/OSgrAEtgmzc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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