SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '168e05f6f90f7b5e975c78d739726097e77351423276826b3bcb70277e824b16' 
  AND token = 'Cp7qxK/bvVyxWhIohcY2TLStNWVs0Q1i2ekwWGcGDrw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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