SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce517887a04da1acd2fb20b5837de0fd95c8813752046d22308c987a7700d947' 
  AND token = 'I+Qh33gHdqT+Z5dYajxL/5dt+1URoXOOmSwMrb288Ho=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}