SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'dd20e1aa1b34b5ff76842201d3b79257c4bde60335a1ab187ea8f683471d5bf2' 
  AND token = 'TzqqEj33Fd3HVJnZkkvXFHrBE4lActEclOCW8i6gl/c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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