SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd14f7327fd320b0af21af98f1280c82472ef543a97a05919d85fc63cb2dc7f7' 
  AND token = 'W97gKrSfUSVlugdp8iRdAttr+r4ISM4z+I9yuRmiftw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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