SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3e9158d25abf264efaac269854e590a2ebfb2d10adbf41e93aeecbcf430c2232' 
  AND token = 'PV2kT8BDbEJHY2YFhYWb1KxAj/9jYbU0UcsAzQnDUmQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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