SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '694ba67eb1acac5014807465da437ddd66d3ad993916a407c1e4b96a6a952a45' 
  AND token = 'RbpeTeSnSWRqgIITl8IKz4qYlsTC51rydou694msOmg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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