SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '3eeac34342709b22acf9e397560bf4f589d311e78b75d67246fc06fddf8b4e6a' 
  AND token = '4Scnwz2LYwz2umTKyOp/nwW7z8KJ0aQP8eDX6r2DPGY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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