SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f7e5884240012d6d53be482aae0622c06c428ba840c68990c610760e6d225998' 
  AND token = 'v1TT0rtMWjRvosdJHAikmpWz3XB0CGXTDObVuFHdmWA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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