SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'abc605655e9f28cd0a75d5091c8d10a0039c226eaa79e02c3fccee41c97ed53f' 
  AND token = 'cpLGPfTQKHbqUCLyqrpuHJ39SdO6g4r/UEa/VRkwGxk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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