SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ee5db4901a692b49c88a6f6be9199d6a7f52f1f9db2adb3e87f33b59ca6e20f2' 
  AND token = 'VDLs1fa1CHgAfCn+XRB8YNnoC+4QdcMkvcR2zqPU1uQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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