SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'f2eb3c5d11b83859a4a66f8e12f945560eb373e7f1cdfaee3c225b3c2dd1d677' 
  AND token = 'x7EK7+49qmfGrSii/88sc7Btz9BVZNnBC2DcdxOR1/w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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