SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f537336a5849c096e3fafea7b83e25de05120535ae82a07bcd3e4d7de22a9415' 
  AND token = 'J9DNgopDPHgL8BnZO6lYQTLzxQXLJRrhG3TQAPotPc0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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