SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a84b360df970bbd5b978d79e36d1e9aba24af2192a0f7607ad408d0162e9affe' 
  AND token = '4QwycPJ08mDH6W1PVbVGYda+LPAgDvSLLVcIySh2IQ8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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