SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed2256adf992c200e8bef575ea67851db5146ba61acf24f6329cf890d3a5c7ae' 
  AND token = '7/FDSRNgE1ATVhHKfgBwNPfB+Ffx1WvP+NpXI5owhd8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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