SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '43a1623c17b4593b83bd539adf5fb9e0d21f722462e9e40bcd8c9d7c19eab37e' 
  AND token = 'XhpFuAYWzkJh2GlEn+3rx/RywV3snj4twxRAaFN4f+k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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