SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd0523e11a8e8a922762fb97566ebcdf4587572347d2c319e8cb33ecb8458cd7' 
  AND token = 'k7JWQwJYBHD0SYjt70MEoWMNv91yUPNYFCAVRmJ/zOk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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