SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '415b5ed8d8b9062e282da0190dad0150cd0bede20acc20bf5f961dd8c6c071f1' 
  AND token = 'SvgOAZztfMoOIYlTnXAwgDtXI5d/UVSBwsfykpoP6ss=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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