SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4d06eb72d87b444436d48374e64dd10687e7b47ae1ff87ed04b4fa038be7eafd' 
  AND token = 'Shs8KKBCLmBq+7Wpk3dOWhhzB0ndVWs2McbEqGXDn2Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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