SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5133c12a40c35c7c41fc326ba7ce6c9f1d86a61766d41e2cc8396378f7e68cf7' 
  AND token = 'cuL6wTXyhlqiAogFxISCTYMvSj/lnLACgPhNTrvzMvo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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