SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '184013df4eb388fbcc8c1e45d19d4a50089b3be6819767e1227d8a5cec267752' 
  AND token = 'bTZqIHeEMWYrwTVKDCOLoKyJX9aEGp18u26eNZs8//U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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